Pumping supply system for delivering at ambient temperature highly viscous material

ABSTRACT

Known pumping supply system consists of supply vat having in its bottom section twin lateral delivery screws extending to a discharge outlet in an end wall and which are rotated in opposite directions. The discharge outlet is flow connected to the intake of a delivery pump. The present improvement adds thereto a pair of oppositely rotated, laterally extending and transversely spaced, flow-directing feeders mounted in the vat relatively closely above the delivery screws. Each feeder has a driven shaft on which is mounted along diametrically opposite sides thereof a pair of sets of a plurality of substantially radially extending and rather closely spaced paddles. These sets of paddles of one feeder shaft are rotated by its shaft out of radial angular phase with those of the other feeder shaft. These rotating feeders cooperatively force the viscous material down into the lateral trough-shaped receiving throat between the delivery screws. This improvement also includes a delivery and return conduit which is flow connected between the discharge opening of the delivery pump and an upper portion of the vat. Between the delivery pump and a terminal portion of this return conduit there is flow connected to the latter one or more supply branch lines to supply the pumped material to one or more use receiving stations. Each branch line may have connected therein a flow rate controlling pump.

United States Patent 11 1 Brown et al.

[ 51 Apr. 22, 1975 PUMPING SUPPLY SYSTEM FOR DELIVERING AT AMBIENTTEMPERATURE HIGHLY VISCOUS MATERIAL [75] Inventors: Joseph L. Brown,Dallas; Don L. Terry, Duncanville, both of Tex.

[73] Assignee: Kentucky Fried Chicken Corporation, Louisville, Ky.

22 Filed: Nov. 6, 1973 21 Appl. No; 413,237

[52] US. Cl. 415/72; 259/6; 222/238 [51] Int. Cl. F04d 3/02; BOlf 7/08;BOlf 15/02 [58] Field of Search 415/72, 73, 74, 11; 259/6,

[56] References Cited UNITED STATES PATENTS 1,209,790 12/1916 Woodcock222/238 1,668,324 5/1928 Kreisingcr 222/238 2,509,379 5/1950 Vasel 259/62,991,870 7/1961 Griffith 259/6 3,114,933 12/1963 Ambrette 259/63,704,076 11/1972 Vasilicvich 415/73 OTHER PUBLICATIONS St. Regis CPFood Equipment and Refrigeration Division Bulletin A-l-SOO."

Primary Examiner-C. J. Husar Assistant Examiner-Louis .l. CasaregolaAttorney, Agent, or F irmWatson Leavenworth Kelton & Taggart [57]ABSTRACT Known pumping supply system consists of supply vat having inits bottom section twin lateral delivery screws extending to a dischargeoutlet in an end wall and which are rotated in opposite directions. Thedischarge outlet is flow connected to the intake of a delivery pump. Thepresent improvement adds thereto a pair of oppositely rotated, laterallyextending and transversely spaced, flow-directing feeders mounted in thevat relatively closely above the delivery screws. Each feeder has adriven shaft on which is mounted along diametrically opposite sidesthereof a pair of sets of a plurality of substantially radiallyextending and rather closely spaced paddles. These sets of paddles ofone feeder shaft are rotated by its shaft out of radial angular phasewith those of the other feeder shaft. These rotating feederscooperatively force the viscous material down into the lateraltrough-shaped receiving throat between the delivery screws. Thisimprovement also includes a delivery and return conduit which is flowconnected between the discharge opening of the delivery pump and anupper portion of the vat. Between the delivery pump and a terminalportion of this return conduit there is flow connected to the latter oneor more supply branch lines to supply the pumped material to one or moreuse receiving stations. Each branch line may have connected therein aflow rate controlling pump.

2 Claims, 4 Drawing Figures PATENTED 3,879,150

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PUMPING SUPPLY SYSTEM FOR DELIVERING AT AMBIENT TEMPERATURE HIGHLYVISCOUS MATERIAL BACKGROUND AND SUMMARY The present invention relates topumping systems featured by oppositely rotated twin lateral deliveryscrews located in the bottom sections of supply vats thereof in which isplaced masses of highly viscous paste material for discharge thereoffrom the vat by the screws through an end wall of the vat to a maindelivery pump.

Such an equipped supply vat is proposed in Bulletin A-l-500 of the CPFood Equipment and Refrigeration Divsion of the St. Regis Company. 1243W. Washington Boulevard, Chicago, Illinois 60607. However, thatequipment called the CP Pumping System" is designed to comparativelylarge scale so as to serve its intended purpose for relatively highcapacity rates of delivery flow. When such equipment is attempted to beused for relatively low capacity operation in the baking industry todeliver uniformly relatively exact amounts of highly viscous butter andstiff margarine or shortening at ambient temperatures, to avoid thedeterioration thereof as to taste and physical characteristics byapplication of liquefying heat, undesirable bridging occurs at therotating delivery screws and pockets of air become entrapped in thedelivered paste material which interferes deleteriously with the desireduniform rates of flow at the receiving dough sheeters, premixers, anddough developers.

These and other undesirable characteristics are efficiently overcome oreliminated by the added features of the present invention.

An object of the present invention is to improve such a pumping supplysystem so that the supply output is at the desired uniform low capacityrate of flow and the delivered flow or flows is or are substantiallyfree of entrapped air pockets.

Another object is to eliminate substantially the ten dency at lowoperational speeds for the paste material in the vat to bridge threadsof the delivery screws which tends to cause air entrapment, and whichassures uniform output flow.

A further object is to provide a delivery conduit which defines a flowpath between the main delivery pump and back to the vat which has agreater flow capacity than the maximum delivery rate capacity of usereceiving means at one or more locations, with each of the latter flowconnected to this delivery conduit by a branch supply line of thedelivery conduit that assures constant positive flow at uniform pressureat the use receiving means with the delivered flow or flows being freeof entrapped air pockets.

Briefly, the added equipment of the present invention includes (1) apair of rotatably driven feeders located in the vat just above the twinrotated discharge screws and (2) the return line in the form ofadelivery conduit extending between the main delivery pump and the vatwith branch line or lines for one or more use receiving means being flowconnected to this delivery conduit.

Each feeder includes a rotatably driven lateral shaft preferably havingits ends supported by bearings carried by the opposed end walls of thevat. Each feeder shaft carries along its length between the vat endwalls a plurality of substantially radially extending paddles whichpreferably are provided in two diametrically opposite sets thereof.These paddles preferably are rather narrow in width and in each set arespaced along the shaft at relatively small distances, e.g., about thewidth of each paddle. The two rotary feeder shafts are driven inopposite directions with that located immediately above one of thescrews being rotated in the same direction as the latter. This causesthe paddles carried by one of the feeder shafts to swing forward towardthe other feeder shaft and downward through the transverse space thatintervenes them, so that the sets of paddles on both shaftscooperatively force the paste materials down into the trough-shapedreceiving throat between the oppositely driven discharge screws, so asto avoid undesirable bridging of the screw blade turns.

The delivery conduit which extends from the discharge opening of thedelivery pump to the branch delivery line or lines, that extends orextend to the one or more use receiving means, has a terminal sectionbeyond this branch line or these branch lines which extends back to thechamber of the vat above the feeders as a return flow line. The flowcapacity of the delivery pump and this delivery conduit is greater thanthe maximum demand of the use receiving means, so that, in operation ofthis pumping supply system, there is always return flow back to the vatchamber.

Other objects of the invention will in part be obvious and will in partappear from reference to the following detailed description taken inconnection with the accompanying drawings, wherein like numeralsidentify similar parts throughout. and in which:

FIG. 1 is an elevational perspective of an embodiment of the pumpingsupply system of the present invention as designed for use in the bakingindustry;

FIG. 2 is a longitudinal sectional view taken substantially on line 22of FIG. I, with parts broken away and others in side elevation, of thesupply vat and delivery conduit extending therefrom toward the deliveryP p? FIG. 3 is an elevational view taken substantially on line 33 ofFIG. 1, with parts broken away, of the end of the vat opposite theoutlet end thereof; and

FIG. 4 is an enlarged transverse sectional view, with parts broken away,taken on line 4-4 of FIG. I, showing the bottom of the section of thesupply vat and the equipment mounted therein.

As will be seen from the drawings the pumping supply system of thepresent invention includes an open top supply vat 10 having a supplychamber 11 defined by a pair of opposed and longitudinally spacedtransverse end walls 12 and 13, a pair of opposed and transverselyspaced sidewalls 14 and 15, and a longitudinally extending bottomstructure 16. As will be seen from FIG. 1, and as is shown in FIG. 4,the supply chamber 11 defined by the supply vat 10 has a bottom section17. The walls of the tank 10 are made of corrosion resistant sheet metalwhich is compatible with and does not deleteriously affect the pastematerial, e.g., highly viscous butter or stiff margarine and shortening,and accordingly may be made of sheeted stainless steel or other sheetmetal which may be painted or coated with an approved plastic.

As will be seen from FIGS. 2 and 4 the exit end wall 12 is provided witha laterally directed outlet which may be in the form of a pair ofdischarge openings 18 and 118. The composite laterally directed outlet,in the form of the pair of outlet openings 18 and 118, feed into amanifold sleeve 19 which is flow connected to the mouth of a truncatedtapered supply tube 21, as will be understood from FIGS. 1 and 2. Thedischarge end 22 of the supply tube 21 is connected to the intake 122 ofa positive displacement pump 23, as will be understood from FIGS. 1 and2, and this pump constitutes delivery pumping means having its intakeflow connected to the vat outlet cooperatively provided by the outletopenings 18 and 118.

As will be understood from FIGS. 2 and 4 a pair of delivery screws 24and are rotatably mounted in the vat chamber bottom section 17 inlateral orientation and closely spaced general parallelism in anysuitable manner. The delivery screws 24 and 25 respectively includeshafts 124 and 125 about each of which are respectively carried spiraledthrust blades 26 and 27. As will be understood from FIGS. 2 and 4 thespiral blade 26 is right handed and the spiral thrust blade 27 is lefthanded, so that as the screw shafts 124 and 125 are rotated in oppositedirection they both cooperatively advance paste material in the vatchamber bottom section toward the discharge vat end wall 12. The shaftof the delivery screw 24 has its back end suitably journaled through thevat end wall 13, to carry, fixed thereon, exterior of the vat chamber, adriving spur gear 28, and the forward end of this screw extendscoaxially through the discharge opening 18 into the tubular manifold 19for suitable journaling therein (not shown).

The journal mounting of the delivery screw 25 is similar to that ofdelivery screw 24, with coaxial extension of its forward end through thedischarge opening 118. As is indicated in FIG. 3 the extending back endof the delivery screw shaft 125 carries exterior of the vat chamber andthe back end wall 13 suitable driving means, such as in the form ofapulley 29 fixed thereon about which is lapped a suitable driving belt30, which may be a chain belt, that in turn is lapped about a drivepulley 31 fixed on the output shaft 32 of a suitable drive motor 33. Thedelivery screw shaft 125 also carries, fixed thereon, a spur gear 34which is meshed with the spur gear 28, so that as the motor 33 rotatesthe delivery screw shaft 125 in clockwise direction, as viewed in FIG.3, spur gear 28 which is meshed with gear 29 rotates the delivery screwshaft 124 in counterclockwise direction.

As will be best understood from FIG. 4 the oppositely rotated drivendelivery screws 24 and 25 define therebetween a lateral trough-shapedreceiving throat 35, into which the paste material loaded into the vatchamber 11 will progressively feed, particularly when suitably urgedinto this throat, for extrusion of the paste material out through thedischarge openings 18 and 118 for progressive delivery through themanifold 19 and the sleeve 21 into the intake 122 of the delivery pump23 at a substantially constant pressure. Since for the particularservice for which this embodiment of the pumping supply system isdesigned, e.g., for the baking industry to supply the stiff butter,margarine or shortening, to a plurality of use receiving means, such asa dough sheeter, a premixer, and a dough developer, the constantpressure of the stiff paste material is to be relatively low, e.g.,approximately 2 pounds. Thus, the mere weight of the mass of pastematerial which is loaded into the vat chamber 11, preferably by hand, isnot sufficient to assure that it will enter between the turns of thedelivery screw blades 26 and 27 without bridging, so as to form airpockets therein unless suitable feeding means is provided in the tankchamber bottom section immediately above these delivery screws toperform this function.

As will be understood from FIGS. 2 and 4 such necessary feeding means isin the form of a pair of oppositely rotated, laterally extending andtransversely spaced flow-directing feeders 36 and 136 that are mountedin the vat chamber bottom section 17 relatively closely above thesedelivery screws 24 and 25 with these including respectively lateralshafts 37 and 137 of similar construction and mounted in similar mannerbetween the vat end walls 12 and 13. For example, feeder shaft 37 isrotatably supported by a suitable journal 38 on back end wall 13 withthe back end of this shaft projecting through this back end wall tocarry thereon and fixed thereto, exterior of the vat chamber 11, drivingpulley 39 and drive spur gear 40. A similar journal 138 rotatablysupports the front end of this feeder shaft 37 upon the discharge endwall 12. Such journals may, for example, be Teflon bearings.

Each feeder shaft, such as 37, carries along its length and fixedthereto a plurality of substantially radially extending paddles 41 and141. Preferably, these paddles are arranged in two diametricallyopposite sets, which may be about 2%inches long and about three-quartersof an inch wide. Thus in each of the two diametrically opposite setsthese paddles 41 and 141 are of relatively narrow width and are spacedlongitudinally along the shaft at relatively short distances apart, suchas about three-quarters of an inch. It is preferred that these paddles41 and 141 be substantially flat and extend substantially radially ofthe axis of the shaft 37 or 137 on which they are mounted, with thepaddles in one set, Le, 41, being staggered longitudinally relative tothose in the opposite set, i.e., 141.

These feeders 36 and 136 are arranged and so driven as to be rotated inopposite directions, i.e, those mounted on shaft 37 as viewed in FIG. 4to be swung counterclockwise and those mounted on shaft 137 to be swungclockwise. Accordingly, the feeder shafts 37 and 137 are rotated inopposite certain directions which cause the paddles carried by each toswing forward toward the other feeder shaft and downward through thetransverse space intervening these feeders cooperatively to cause themto force the paste material down into the trough-shaped receiving throat35 between the discharge screws 24 and 25. It is also preferred that thepaddles 41 and 141 which are embodied in feeder 36 and those which areembodied in feeder 136 are arranged out of radial angular phase withrespect to each other, e.g., at right angles or This out of phaseangular relationship of the paddles of one feeder with respect to thoseof the other feeder assures that there will be no undesirableinterference with the downward forcing action of the paddles of one withrespect to those of the other, and also elimination of any possiblephysical interference of the paddles of one feeder with respect to thoseof the other feeder. It will also be noted that these respective feedersare rotated in the same directions as are the discharge screws locatedimmediately therebelow, i.e., discharge screw 24 and feeder 36 arerotated in counterclockwise direction, and discharge screw 25 and feeder136 are rotated in clockwise direction.

As will be understood from FIGS. 2 and 3 the projecting back end ofdischarge screw shaft 124 also carries, fixed thereto, beyond spur gear28 a pulley 42. An endless belt 43 is lapped about screw pulley 42 and ls feeder pulley 39 for drive of the latter from the former. Feeder shaft137 has its projecting back end carrying, fixed thereto, a similar spurgear 140 which is meshed with spur gear 40. Thus the motor 33 drivesboth of the feeders 36 and 136 and the discharge screws 24 and 25simultaneously in the desired indicated directions.

The delivery pump 23 has its discharge outlet at 44 connected todelivery conduit means or. a pipe 45 which leads to use receiving means.For this purpose delivery pipe'4l may carry a T-fitting 46 which has onearm flow connected to the pipe 45 and the other arm connected to asuitable branch line 47 which is to lead to one use receiving means orequipment, such as a cer- I tain one of a dough sheeter, a premixer, anda dough developer. A vertical pipe 145 is mounted to the leg of theT-fitting 46 and has branch lines 48 and 49 flow connected thereto. Thebranch lines 48 and 49 respectively feed to additional use receivingmeans such as the other two of the three equipments mentioned above.Thus these branch lines 47, 48, and 49, and their respective extensions147, 148, and 149 provide supply conduits for three different stations,e.g., No. 1, No. 2, and No. 3. Preferably, each of these three supplybranch lines has inserted therein a separate flow rate controlling pump.Each such pump (50 or 150 or 250) is driven by a speed controlled motorand the speed thereof determines the rate of delivery output of thefeeder line in which it is inserted.

Flow through the upright run 145 of the delivery conduit is connected bya T-fitting 51 (which may be an elbow) to a terminal section pipe 52which leads back to the vat chamber 11 for return to this vat chamber ofthe excess of paste material above the composite demand of the threestation branch lines 47, 48, and 49 and their flow rate controllingpumps 50, 150, and 250. In other words, the delivery conduit meansdefines a direct return flow path from the discharge opening of thedelivery pump 23 back to the vat chamber for discharge into the latterpreferably at a point above the vat chamber bottom section. lf it isdesired to provide a removable cover for the vat the terminal section 52of the delivery conduit may extend through a suitable opening in one ofthe sidewalls of the vat near the top of the latter, then to extend downto the desired point of discharge.

It will be noted from FIG. 1 that the upright run or section 145 of thedelivery conduit preferably also includes, for convenience, anotherT-fitting 53, so that the leg 54 thereof may serve to communicate theinterior of such conduit with a suitable pressure meter 55. TheT-fitting 51 may also house, for convenience, a flow controlling valveof conventional or suitable construction, with an externally accessiblehand knob 56 being provided thereon to adjust the size of the flowpassage therethrough. Such adjustable flow control valve may thus beadjusted so that the pressure in the return line may be maintained at avalue which is best suited to assurance that the returned excess of thebuttery composition or paste material being delivered by the pumpingsystem is kept substantially free of air voids. All of the runs orsections and fittings of such delivery conduit and return line desirablymay be formed of suitable material, such as stainless steel, that iscompatible with the composition being pumped therethrough, so as not tocontaminate the latter, particularly when it is a foodstuff.

As a result of this delivery conduit means and its branch lines there isfeed of the paste material to the three different'stations at constantpressure. The three feed pumps 50, 150, and 250 in the three delivery orsupply branch lines which are operating at constant pressure, provide auniform and exact or precise rate of flow of the paste material to eachstation. Since the paste material is not preheated to increase thefluidity thereof for facilitating the operation of this supply anddelivery system deleterious effect of heat on flavor is avoided. Theinsertion of the unheated stiff butter, margarine, or shortening betweenlayers of the dough by such a continuous process assures the productionof a more uniform product and gives a prebuttered effect whileeliminating any need for heating butter when the roll is to be readiedfor eating. Also, by avoiding the heating of the buttering material thedifficult cleaning process of the equipment is materially and desirablyreduced. By virtue of the supply of the stiff butter material at thedeveloper for distribution throughout the dough assures a more uniformand desirable taste, and the supply thereof at the premixer providesdesired lubrication so that the otherwise stiff dough can be pumpedwhile avoiding lumping. It is highly desirable in the baking industry tokeep the dough at the lowest possible temperature so as to preventmelting of the buttering material and delivery by the present pumpingsupply system to the respective stations in the manner indicatedprevents excessive heat buildup.

It will thus be seen that the objects set forth above, among those madeapparent from the preceding description, are efficiently attained and,since certain changes may be made in the above construction withoutdeparting from the scope of the invention, it is intended that allmatter contained in the above description or shown in the accompanyingdrawings shall be interpreted as illustrative and not in a limitingsense.

Having described our invention, what we claim as new and desire tosecure by Letters Patent is the novel subjects matter defined in thefollowing claims:

1. A pumping supply system for delivering at ambient temperature highlyviscous and butter-like paste material at a relatively uniform rate offlow and substantially free of air voids comprising, in combination;

1. a supply vat defining a supply chamber having a lateral bottomsection provided at one end with a laterally directed outlet;

2. delivery pumping means having its intake flow connected to the vatoutlet;

3. a pair of oppositely rotated and laterally extending driven deliveryscrews in the bottom section of said vat chamber extending in closelyspaced general parallelism to said vat outlet which define therebetweena lateral trough-shaped receiving throat;

4. a pair of oppositely rotated, laterally extending and transverselyspaced, flow-directing feeders mounted in said vat chamber bottomsection relatively closely above said delivery screws, each comprising adriven lateral shaft carrying along its length and fixed thereto aplurality of substantially radially extending paddles; and

5. means to drive said feeder shafts in opposite certain directions thatcause said paddles on each of said feeder shafts to swing forward towardthe other feeder shaft and downward through the transverse spaceintervening said feeders cooperatively to cause the latter to force thepaste material down into the trough-shaped receiving throat between saidscrews;

6. said delivery pumping means having its discharge opening connected todelivery conduit means leading to use receiving means which demands lessthan the maximum delivery rate capacity of the delivery pumping meansand said delivery conduit means, the latter having a terminal sectiondefining a flow path back to said supply vat for return to the latter ofthe excess above the demand of the use receiving means; and

7. said use receiving means comprising a plurality of separate usereceiving stations with a plurality of supply branch lines connected tosaid delivery conduit means between the delivery pumping means and theterminal return section with each branch line leading to one of saidstations, each branch line including a separate flow rate controllingpump. 2. The pumping supply system as defined in claim 1 characterizedby said delivery conduit means defining a direct return flow path fromthe discharge opening of said delivery pumping means back to theinterior of said vat at a point of discharge above said vat chamberbottom section said plurality of supply branch lines for the separateuse receiving stations being directly flow connected to said conduitmeans between the discharge opening of said delivery pumping means andthe terminal return section of said conduit means.

1. A pumping supply system for delivering at ambient temperature highlyviscous and butter-like paste material at a relatively uniform rate offlow and substantially free of air voids comprising, in combination; 1.a supply vat defining a supply chamber having a lateral bottom sectionprovided at one end with a laterally directed outlet;
 1. A pumpingsupply system for delivering at ambient temperature highly viscous andbutter-like paste material at a relatively uniform rate of flow andsubstantially free of air voids comprising, in combination;
 1. a supplyvat defining a supply chamber having a lateral bottom section providedat one end with a laterally directed outlet;
 2. delivery pumping meanshaving its intake flow connected to the vat outlet;
 3. a pair ofoppositely rotated and laterally extending driven delivery screws in thebottom section of said vat chamber extending in closely spaced generalparallelism to said vat outlet which define therebetween a lateraltrough-shaped receiving throat;
 4. a pair of oppositely rotated,laterally extending and transversely spaced, flow-directing feedersmounted in said vat chamber bottom section relatively closely above saiddelivery screws, each comprising a driven lateral shaft carrying alongits length and fixed thereto a plurality of substantially radiallyextending paddles; and
 5. means to drive said feeder shafts in oppositecertain directions that cause said paddles on each of said feeder shaftsto swing forward toward the other feeder shaft and downward through thetransverse space intervening said feeders cooperatively to cause thelatter to force the paste material down into the trough-shaped receivingthroat between said screws;
 6. said delivery pumping means having itsdischarge opening connected to delivery conduit means leading to usereceiving means which demands less than the maximum delivery ratecapacity of the delivery pumping means and said delivery conduit means,the latter having a terminal section defining a flow path back to saidsupply vat for return to the latter of the excess above the demand ofthe use receiving means; and
 7. said use receiving means comprising aplurality of separate use receiving stations with a plurality of supplybranch lines connected to said delivery conduit means between thedelivery pumping means and the terminal return section with each branchline leading to one of said stations, each branch line including aseparate flow rate controllinG pump.
 3. a pair of oppositely rotated andlaterally extending driven delivery screws in the bottom section of saidvat chamber extending in closely spaced general parallelism to said vatoutlet which define therebetween a lateral trough-shaped receivingthroat;
 4. a pair of oppositely rotated, laterally extending andtransversely spaced, flow-directing feeders mounted in said vat chamberbottom section relatively closely above said delivery screws, eachcomprising a driven lateral shaft carrying along its length and fixedthereto a plurality of substantially radially extending paddles; and 5.means to drive said feeder shafts in opposite certain directions thatcause said paddles on each of said feeder shafts to swing forward towardthe other feeder shaft and downward through the transverse spaceintervening said feeders cooperatively to cause the latter to force thepaste material down into the trough-shaped receiving throat between saidscrews;
 6. said delivery pumping means having its discharge openingconnected to delivery conduit means leading to use receiving means whichdemands less than the maximum delivery rate capacity of the deliverypumping means and said delivery conduit means, the latter having aterminal section defining a flow path back to said supply vat for returnto the latter of the excess above the demand of the use receiving means;and
 7. said use receiving means comprising a plurality of separate usereceiving stations with a plurality of supply branch lines connected tosaid delivery conduit means between the delivery pumping means and theterminal return section with each branch line leading to one of saidstations, each branch line including a separate flow rate controllinGpump.